Process and apparatus for strand treatment



April 29, 1969 R. K. STANLEY- PROCESS AND APPARATUS FOR STRAND TREATMENT Filed Sept. 29, 1967 United States Patent 3,440,699 PROCESS AND APPARATUS FOR STRAND TREATMENT Robert Kenneth Stanley, Media, Pa., assignor to Techniservice Corporation, Lester, Pa., a corporation of Pennsylvania Filed Sept. 29, 1967, Ser. No. 671,818 Int. Cl. D06c 3/00, 19/00; D02g 3/00 US. Cl. 281 20 Claims ABSTRACT OF THE DISCLOSURE This invention relates to treatment of textile strands and provides particularly for improved stabilization of crimp therein by withdrawing crimped strand through a. particulate bed spaced from any accumulated mass of strand, especially a steam-heated bed of solid spherules. Such a bed is useful at the exit end of a stuffer crimper.

Stulfer crimping is a well known technique for imparting bulk, cover, and extensibility to textile strands, especially those having component continuous filaments. Examples of stufifer crimpers appear in my US. Patents 3,279,025 and 3,280,444. For certain uses the extensibility of the crimped product may be greater than desired,

especially at relatively low tensions, and a dependable method of stabilizing the crimp to reduce the extensibility is desirable. Previous attempts to do so have not been entirely satisfactory, whether because of unevenness of result, difficulty of application, or otherwise.

A primary object of the present invention is an improved crimp stabilization of textile strands.

Another object is reduction in extensibility of stuifercrimped textile strands.

A further object is provision of apparatus for accomplishing the foregoing.

Other objects of this invention, together with means and methods for attaining the various objects, will be apparent from the following description and the accompanying diagrams.

FIG. 1 is a front elevation, part-1y schematic in form, of a stutter crimper incorporating the present invention;

FIG. 2 is a side elevation of the apparatus of FIG. 1;

FIG. 3 is a sectional plan of the same apparatus, taken at III-III on FIG. 2;

FIG. 4 is an enlarged sectional elevation of a portion of the apparatus, taken at IV-IV on FIG. 2; and

FIG. 5 is a sectional plan taken at VV on FIG. 4.

In general, the objects of the present invention are accomplished, in a stutfer crimper having a stufiing chamber in which crimped textile strand accumulates before being withdrawn therefrom, by means of a particulate bed spaced from the strand accumulation and through which the crimped strand is withdrawn. The bed preferably comprises solid spherules and is impregnated with steam.

FIG. 1 shows from the front, FIG. 2 from the side and FIG. 3 in plan (sectioned through the stuifing chamber) stutter-crimping apparatus including, in the direction of strand passage therethrough as indicated by arrows, a pair of forwarding rolls 11, 11' gripping strand on opposite sides, and preheater 12 which is activated by internal electrical resistance heating elements or by injection of steam or other hot fluid. After passing therethrough the strand passes between pair of feed rolls 13, 13', and stufiing chamber 14, which has its entrance juxtaposed to the nip of the feed rolls. The stuffing chamber terminates at its exit in housing 15, from which the strand is withdrawn by additional pair of rolls 16, 16. The chamber is supported on the front wall of frame 22, which has an inverted U-shape in side elevation.

3,440,699 Patented Apr. 29, 1969 ice Shafts 23, 23' for respective feed rolls 13, 13' are journaled in the front and rear walls of the frame and have intermeshing gears 33, 33 thereon behind the rear wall of the frame. Shaft 23 also has pulley 29 thereon. Motor 31 on the upper horizontal surface of the frame has shaft 32 on which is pulley 39. Belt 34 interconnects pulleys 39 and 29 to transmit rotational force to the gears, shafts, and the feed rolls themselves. The direction is such as to feed or stuff the strand by and between the counterrotating feed rolls into the stuffing chamber, wherein it assumes crimped configuration upon encountering compressed accumulation 10a of strand already therein, as shown in FIG. 4.

Crimped strand 10' withdrawn from the strand accumulation in the chamber is withdrawn by rolls 16, 16' through the upper part of the chamber and through the nip of pair of tensioning rolls 40, 40 mounted therein on axles 41, 41' journaled in the chamber wall. Axle 41' is extended outside and carries retarding roll 43 over which passes belt 44, which is fastened at its upper end to the chamber wall by clip 45 and at its lower end carries weight 46. Drag of the belt on the retarding roll imparts tension to the crimped strand passing through the nip of the tensioning rolls. The tension is adjustable by varying weight 46.

Housing 15 into and through which the strand passes has inverted conical wall 51 defining a bed open upward and having entrance 50 at the apex of the cone at the bottom of the bed. The bed contains numerous solid spherules made of ceramic or other suitable material too large to fall out through the strand entrance. The strand is withdrawn upwardly by rolls 16, 16 and passes among the spherules and out from the top of the bed, the resultant strand being denoted as 10" in recognition of the fact that its characteristics differ somewhat from those of initially crimped strand 10'. The bed is surrounded laterally by a hollow jacket, which receives entrance pipes 53 and 53' communicating therewith through the outer wall of the housing. The bottom wall has apertures 55, 55' of very small cross-section therein for drainage of any condensate such as water condensed from steam carried by the pipes to the jacket from a conventional generator thereof (not shown). The steam enters the bed through apertures 57 near the base thereof, each of which is provided with a low-pressure valve, as by the spring 58 and ball 59 type of combination shown in FIG. 5.

In accordance with this invention the strand is stufter crimped and then is withdrawn from the accumulation thereof compressed in the stufiing chamber and is withdrawn through the particulate bed, which is shown as comprising solid spherules large in diameter as compared with the strand. Immediately before entering the bed the strand is under a tension on account of the weight of strand suspended above the accumulation from which it was withdrawn and whatever tension is applied by the tensioning rolls and associated components of the restraining means, which could be replaced by a long length of supported strand although to do so would be wasteful of equipment, materials and space otherwise conserved by using such restraining means. The strand must not pass directly from the compressed mass to the bed without imposition of tension therebetween or the crimp will be impaired.

Passage through the bed increases the tension on the crimped strand in a graduated manner and thereby withdraws part of the crimp imparted thereto in the stuffing chamber. As indicated above, the bed is preferably heated, and steam may be injected int-o it, with the result of improving stabilization of the crimp configuration at the re sulting length, which is intermediate between the original uncrimped length and the first crimped length. Steam at a pressure from several to a dozen pounds per square inch above atmospheric can be used. With hydrophilic strand compositions the ambient moisture may suffice upon injection of otherwise dry hot gas, such as air. When the strand composition is particularly thermosensitive, air at ambient temperature can be used with some success, althrough moderate heating may still be desirable, especially at relatively high processing speeds. In general, it is preferred to keep the strand about as warm as it was when it passed into the chamber entrance for so long as any change in the configuration thereof is being effected, and preferably without overheating it.

As an example, a 1040 denier 6-nylon strand of 68 filaments when stutter crimped had an elongation or extensibility of 10% under a tension of 100 grams. The tension on it before passage through the bed, which was heated to 150 C. by superheated steam, was about 50 grams, and upon leaving the bed was about 150 grams. Under 100 grams tension the elongation or extensibility thereof proved to be only 1%. The same reduced extensibility prevailed throughout normal winding and handling of the strand, even when reheated weeks later.

I claim:

1. Aftertreatment for crimped textile strands comprising pulling a crimped textile strand through a steam-impregnated particulate bed and thereby reducing the crimp level and stabilizing the crimp at reduced level.

2. Process according to claim 1, wherein the elongation of the crimped strand under tension of about one-tenth gram per denier is reduced thereby to a minor fraction of its original value.

3. Process according to claim 2, wherein the original elongation of the crimped strand was on the order of ten percent and the final elongation thereof is on the order of one percent.

4. Process according to claim 1, wherein the input tension on the crimped strand before entering the particulate bed is less than one-tenth gram per denier, and the output tension thereon upon leaving the bed is several times as great.

5. In a stuffer crimper having a stufiing chamber in which crimped textile strand accumulates before being withdrawn therefrom, the improvement comprising means for applying restraining tension to a strand withdrawn from the strand accumulation and being withdrawn from the chamber, and a particulate bed spaced from the restraining means and through which the strand is then withdrawn.

6. Stuffer crimper according to claim 5, wherein the restraining means comprises a roll arranged to come into essentially non-slipping contact with the strand.

7. Stuffer crimper according to claim 6, including frictional means interconnected to the roll to retard the rotation thereof.

8. Stuifer crimper according to claim 5, wherein the particulate bed comprises a multiplicity of spherules and a container thereof, the container having below the surface of the bed an entrance for the strand and having above the surface of the bed an exit for the strand, and

including means to withdraw the strand from the chamber, then past the restraining means, and thereafter through the bed.

9. Stutfer crimper according to claim 8, wherein the container constrains the bed into an inverted conical shape, with the apex thereof adjacent the entrance for the strand,

10. Stutfer crimper according to claim 8, wherein the container is provided with a heating jacket.

11. Stuffer crimper according to claim 10, wherein the heating jacket communicates with the container interior adjacent the bottom of the bed.

12. Stuffer crimper comprising a vertical confining chamber having at its lower end an entrance for textile strand to be stuffed thereinto and to be accumulated temporarily and be crimped therein, feed means for stufling strand into the chamber entrance, a particulate bed located near the upper end of the chamber and above the maximum level at which crimped strand normally accumulates before being withdrawn from the chamber, the chamber being free of non-particulate strand-impeding means at and above the level of the bed, and means for withdrawing the crimped strand from the accumulation thereof and then through the particulate bed.

13. Stutfer crimper according to claim 12, wherein the particulate bed comprises solid spherules.

14. Stuffer crimper according to claim 12, wherein the particulate bed is heated 15. Stuffer crimper according to claim 14, wherein the particulate bed is heated by injecting steam therein.

16. Stuffer crimper comprising a vertical confining chamber having at its lower end an entrance for textile strand to be stuffed thereinto and to be accumulated temporarily and be crimped therein, feed means for stufling strand into the chamber entrance, a particulate bed located near the upper end of the chamber and above the maximum level at which crimped strand normally accumulates before being withdrawn from the chamber, means for withdrawing the crimped strand from the accumulation thereof and then through the particulate bed, and means for injecting steam into the bed.

17. Stutfer crimper according to claim 16, wherein the steam-injection means includes valve mechanism to limit the pressure at which the steam is injected into the bed.

18. Stuffer crimper according to claim 16, including strand-tensioning means spaced below the particulate bed and above the level of normal crimped strand accumulation in the chamber.

19. In a stutter crimper having a particulate bed through which crimped strand is pulled, the improvement comprising a wall portion in the configuration of an inverted cone housing the particulate bed and having at its apex an opening large enough to pass the strand but too small to pass particles from the particulate bed.

20. Apparatus according to claim 19, wherein the conical wall portion has apertures therethrough for admitting treating fluid to the particulate bed, and including means for supplying treating fluid to those apertures.

References Cited UNITED STATES PATENTS 2,949,659 8/1960 Heijnis et al. 2,971,242 2/1961 Doleman et al 28-62 3,153,271 10/1964 Eshuis. 3,153,837 10/1964 Schippers ct al.

FOREIGN PATENTS 264,406 6/ 1964 Netherlands. 883,119 11/1961 Great Britain.

LOUIS K. RIMRODT, Primary Examiner.

US. Cl. X.R. 28-72 

